Conventionally, a double-sided label strip or continuum with no backing sheet is known. It is made by laminating a first sheet and a second sheet. On each back side or inward facing surface of the first sheet and the second sheet, an adhesive and a remover are formed alternately at positions where the adhesive of one sheet attaches temporarily to the remover of the other sheet.
When the double-sided label continuum without the backing sheet as described above is clamped with pressure between a platen roller and a thermal head and is printed, the adhesive is spread by the pressure. This generates problems because the adhesive may attach to the neighboring adhesives or to another sheet, or the adhesive may protrude from the outer edge of the label. In order to prevent such problems, a double-sided label continuum is used in which a gap is provided respectively between neighboring adhesives on the surface of a sheet.
FIG. 7 is a cross-sectional view of a double-sided label continuum viewed in a direction perpendicular to a label feeding direction, where the double-sided label continuum L has stripes or strips of adhesives 52 extending along the feeding direction and arranged with a predetermined gap 58 between neighboring adhesives. The continuum is clamped with pressure between a platen roller 59 and a thermal head 60, where the continuum is printed and fed. The double-sided label continuum L is comprised of a first sheet 50, a second sheet 51, an adhesive 52, in several stripes and a remover 53 also in several stripes. The first sheet 50 is comprised of a first coloring layer 54 and a first base material 55. A back side surface of the first coloring layer 54 and a front surface of the first base material 55 are bonded. The second sheet 51 is comprised of a second coloring layer 56 and a second base material 57, and a back side, inward facing surface of the second coloring layer 56 and a front, outward facing surface of the second base material 57 are bonded so that the first sheet 50 is bonded. On the back side, inward facing surfaces of the second base material 57 and the first base material 55, an adhesive 52 and a remover 53 are applied alternately, extending linearly parallel to the feeding direction. The adhesive stripes on the first sheet's surface alternate across the continuum with the adhesive stripes on the second sheet's surface, and the removers similarly alternate. Further, each adhesive stripe adhered to one sheet meets a remover on the other sheet. As a result, the adhesive 52 of a sheet adheres temporarily to the remover 53 of another sheet. A width G of the adhesive 52, in a direction is perpendicular to the coating direction thereof, is set smaller than a width of the remover 53. When the adhesive 52 and the remover 53 are attached temporarily, they are arrayed across a gap 58 having a width H perpendicular to the coating direction of the adhesive 52. Because a coating thickness of the adhesive 52 is thicker than a coating thickness of the remover 53, each adhesive 52 does not bond to the neighboring adhesives 52, even if the adhesive 52 is spread by the pressure applied between the platen roller 59 and the thermal head 60.
However, when printing is made on the double-sided label continuum having the above described gap 58, this generates a problem that printing precision decreases, because appropriate pressure necessary for printing is not applied to a portion of the coloring layer which is pressed to the platen roller 59 through the gap 58 and performs printing, the heat generation of the thermal head 60 is not transmitted to the coloring layer, and so printing is not made in the part.